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  1. Giraph
  2. GIRAPH-88

Message count not updated properly after GIRAPH-11

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    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: 0.1.0
    • Fix Version/s: 0.1.0
    • Component/s: None
    • Labels:
      None

      Description

      Email from ssc@apache.org

      Hi,

      I updated to the latest trunk (after the GIRAPH-11 commit) and wanted to
      continue to work on GIRAPH-51 where I use a small toy graph to test
      SimpleShortestPathVertex.

      Unfortunately my code did not work anymore and I guess I tracked it down
      to the fact that vertex that voted to halt are not reacted anymore when
      new messages arrive.

      In SimpleShortestPathVertex every vertex always votes to halt and only
      gets reactivated when a shorter path to it has been found. However my
      test run always finished after superstep 0.

      I don't know too much about Giraph's internals yet, but my guess is that
      the number of sent messages is not tracked correctly anymore. Therefore
      giraph finishes the algorithm (as all vertices voted to halt) although
      there should still be messages in the pipeline.

      I think I tracked it down to this behavior:

      GraphMapper declares a variable workerSentMessages = 0 and never
      increases it. This variable is given to
      BspServiceWorker.finishSuperstep() which writes it to zookeeper and uses
      it to compute the GlobalStats afterwards, which are used to decide
      whether a new superstep has to be scheduled. As it has never been
      increased, the algorithm will always stop when all vertices voted to halt.

      It would be great if someone could confirm/disprove this speculation and
      help me to continue work on GIRAPH-51

        Attachments

        1. GIRAPH-88.diff
          5 kB
          Avery Ching

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            • Assignee:
              Unassigned
              Reporter:
              aching Avery Ching
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              Dates

              • Created:
                Updated:
                Resolved: